Safety closure



Sept. 25, 1962 s. N. GLASBRENNER 3,055,524

SAFETY ACLOSURE 2 Sheets-Sheet 1 Filed April 5, 1961 INVENTOR STANLEY N. GLASBRENNER Ihm muil'.

ATTORNEY Sept. 25, 1962 s. N. GLASBRENNER 3,055,524

SAFETY cLosuRE Filed April 3, 1961 2 Sheets-Sheet 2 L ILT y INVENTOR STANLEY N. GLASBR ENNER ATTORNEY `mal conditions.

United States Patent O 3,055,524 SAFETY CLOSURE Stanley N. Glasbrenner, West Hemplield Township, Lancaster County, Pa., assignor to Armstrong Cork Company, Lancaster, Pa., a corporation of Pennsylvania Fiied Apr. 3, 1961, Ser. No. 100,166 2 Claims. (Cl. 21S-9) This invention relates to a safety closure, and more particularly to a closure which can be applied and removed easily from a container by one having knowledge of its operation, but is relatively safe so far as removal by children is concerned.

In the packaging of many household commodities such as medicines, it is highly desirable that the container be equipped with a closure which cannot be removed by children, but which can be removed readily lby those lfamiliar with the manner of operation of the device.

The particular device here under consideration has a conventional screw-type closure which ts in tight sealing engagement with the lip of the container by reason of the screw threads or other container-engaging means and a suitable sealing liner. The particular liner is selected to suit the specific contents of the container. This inner or primary closure is retained within an outer shell .and the retention means is such that the two clo sures are maintained in axial lalignment with one another but can rotate with respect to one another in at least one direction when torque is applied to the outer shell. The respective diameters of the inner closure and the outer shell are such that the inner closure is received within the outer shell with sutiicient clearance that they can rotate freely with respect to one another with insuflicient frictional -drag for the outer shell to rotate the inner closure when torque is applied. When the two members are in their assembled position, the inside of the top portion of the outer shell and the exterior of the top portion of the inner closure are in juxtaposition and rotate freely -about the same central axis. Means are provided to hold the top of the outer shell away from the top of the inner closure under nor- The lforce by which these are held apart is such that it can be overcome by the application of downward pressure to bring them into interlocking engagement for rotation with one another. Upon the application of downward pressure to the outer shell, engaging means positioned on the bottom surface of the top of the outer shell mesh with engaging means on the top surface of the inner closure. When these engaging means are in mesh, rotation of the outer shell rotates the inner closure for removal from the container.

In one embodiment of the invention the outer surface of the skirt of the inner closure is provided with ratchet teeth which are engaged by ratchet teeth in the inner surface of the skirt of the outer shell yas the assembly is rotated into the threads of a container so that the exertion of torque to the outer shell will transmit torque to the inner shell `for application of the assembly to a container.

In this embodiment, the inner closure and the outer shell will always rotate together lfor application to a container, `but require the exertion of downward pressure to lock the two together to remove the assembly from a container.

In order that the invention may be more readily understood, it will be described in connection with the attached drawing in which FIG. l is a top plan view of the inner closure;

FIG. 2 is a bottom plan view of the interior of the outer shell;

FIG. 3 is a cross-sectional view of the two members in assembled position for use on a container;

3,055,524 Patented Sept. 25, 1962 ICC FIG. 4 is a top plan View of a modified form of the inner closure;

FIG. 5 is a bottom plan view of a modified form of the outer shell; and

FIG. 6 is a crossesectional view of the two modified members in assembled position for use on a container.

Referring to FIG. 1 there is shown an inner closure having a depending skirt 2 which carries on its inner surface a helical thread 3 (FIG. 3) or other containerengaging means to hold the closure in firm, sealing engagement on the container. In the center of the top portion of said inner closure, there is provided an upwardly projecting domed area 4. Extending radially therefrom are a plurality of grooves 5 leaving upstanding areas 6 positioned between adjacent grooves 5. The dome 4 extends upwardly to a height substantially equivalent to the height of the upstanding areas 6 located be' tween the grooves S.

The outer shell 7 (FIG. 2) has an inner diameter slightly in excess of the outer diameter of the skirt of the inner closure 2. At the lower extremity of the skirt `of the outer shell 7 there is provided an inwardly projecting ring 8 (FIG. 3) which snaps over the bottom extremity of the skirt of the inner closure 2 to hold the two members together on the same axis but permitting relative rotation with respect to one another.

The under surface of the top of the outer shell is provided with a downwardly extending dome-shaped projection 9 which is in axial alignment with the domeshaped projection 4 on the inner closure when the two closures are tted together and held by means of the retention ring 8 as described above. Extending radially from the downwardly projecting dome 9 are a plurality of downwardly extending ribs 10 which are of a width slightly less than the width of the grooves 5 in the top surface of the inner closure. These ribs in the embodiment here illustrated are present in half the number of the grooves 5. The downwardly extending domeshaped projection 9 extends slightly below the lower extremity of the ribs 10 so that when the two domeshaped projections are in engagement with one another the ribs 10 will not be in interlocking engagement with the grooves 5.

The inner closure is preferably made of a relatively hard non-yielding plastic material such as polystyrene, urea, Bakelite, or the like, While the outer shell is made of a more flexible resilient material such as polyethylene or polypropylene. The area 11 between the dome-shaped projection 9 on the outer shell and the ribs 10 is rather thin so that upon exertion of downward pressure on the area 12 on the top surface of the outer shell the two dome-shaped portions will no-t compress but rather the shell w-all in the area 11 will iiex, permitting the ribs 10 to tit into grooves 5, locking the two elements together. When in this locked position, if torque is applied to the outer shell, it will be transmitted to the inner closure, and it can -be unscrewed or tightened, depending on the direction of rotation.

In the operation of the device of this invention, the closure assembly is screwed on the container by exerting digital pressure downwardly on the outer shell so that the ribs 10 extend into the grooves 5 and rotate the inner closure on the threads of the container until the inner closure is in sealing engagement with the 4lip of the container. When no digital pressure is exerted on the outer shell, this closure is free to rotate by reason of the two cooperating dome-shaped projections 4 and 9 holding the ribs 10 away from the grooves 5 so that the outer closure can freely rotate over the inner closure. When it is desired to remove the closure assembly from the container, downward digital pressure is again exerted in the area of the outer shell designated by the numeral 12. This pressure causes the projections to mesh with the grooves 5, and continued torque applied to the outer shell will rotate the inner closure and remove it from its ysealing position on the container.

In the modified embodiment shown in FIGS'. 4, 5 and 6, the inner closure is provided with ratchet teeth 13 on the exterior of the skirt 2, and the outer shell is provided with complementary ratchet teeth 14 on the interior of the skirt 6. These teeth 13 and 14 are so designed that they will lock to rotate the two closure members together when torque is applied in the direction to screw the assembly onto a container, but will not lock when torque is applied in the opposite direction. In other words, in this modification the two elements will 4always rotate together when they are being applied to a container but will rotate with respect to one another when torque is applied in the opposite direction unless downward pressure is applied to cause the intermeshing members to engage one another, in which event torque applied to the outer shell will be transmitted to the inner closure, and the same can be removed from the container.

It will Ibe obvious from this description that I have developed a safety closure which can be securely placed on a container and cannot be unscrewed by children without suicient strength and knowledge to manipulate the two elements for cooperative rotation to unscrew the closure from the container.

I claim:

1. A safety closure assembly comprising an inner closure having a top portion to cover the mouth of a container and a skirt portion to t over said container immediately adjacent the opening, threads on said inner closure skirt for engagement with complementary threads on the container, an outer shell of a size to receive an inner closure with su'icient clearance to permit relative rotation of the outer shell with lrespect to the inner closure, means for maintaining the outer shell and inner closure in axial alignment, ratchet teeth in the inner skirt of the outer shell for engagement with complementary ratchet teeth in the outer skirt of the inner closure for engagement to rotate the two with one another in the direction moving into the threads of the container, radial grooves in the top of the inner shell and radial ribs in the bottom surface of the outer shell for engagement with the radial grooves on the inner closure, an upwardly extending dome on said inner closure and a downwardly extending dome on said outer shell to keep the ribs out of the grooves, said domes being in axial alignment and being yieldable under pressure to permit said ribs to engage in said grooves.

2. A safety closure assembly comprising an inner closure having a top portion to cover the mouth of a container and a skirt portion to lit over said container immediately adjacent the opening, threads on said inner closure skirt for engagement with complementary threads on the container, a exible resilient outer shell of a size to receive an inner closure with sufiicient clearance to permit relative rotation of the outer shell with respect to the inner closure, means for maintaining the outer shell and inner closure in axial alignment, ratchet teeth on the inner skirt of the outer shell for engagement with complementary lratchet teeth on the outer skirt of the inner closure for engagement to rotate the two with one another in the direction moving into the threads of the container, radial grooves in the top of the inner shell and radial ribs in the bottom surface of the outer shell for engagement with the radial grooves in the inner closure, an upwardly extending dome on said inner closure and a downwardly extending dome on said outer shell to keep the ribs out of the grooves, said domes being in axial alignment and being yieldable under pressure to permit said ribs to engage in said grooves.

References Cited in thetile of this patent UNITED STATES PATENTS 2,980,274 Gould Apr. 18, 1961 FOREIGN PATENTS 559,264 Belgium Aug. 14, 1957 

